Start laying out options for large-scale riverfront redevelopment in Nashville and the questions come quickly: What will it cost? Who will pay for it? And who will make it happen?

The short answer, says Gavin McMillan of Hargreaves and Associates, is that nobody knows yet. But for clues about the process, a host of similar riverfront projects in other cities can provide some insight.

Hargreaves and Associates presented a redevelopment plan and study of Nashville's riverfront to the public on Aug. 24. Commissioned by the Metro Nashville Parks Department and U.S. Army Corps of Engineers, Hargreaves is leading a team of design firms through the six-month study and planning process. Two more meetings are planned for September and October. In the latter meeting, costs and implementation strategies will be discussed.

Meanwhile, McMillan pointed to projects in other cities - some of which involved Hargreaves - as examples.

Cities have spent anywhere from $30 million to $240 million in public dollars on their riverfront redevelopments. Among those Hargreaves studied, there's a consistent return of $3 to $6 in private investment for every $1 of public money spent.

Pittsburgh, for example, has its redevelopment sectioned into two areas: North Shore and SouthSide Works. SouthSide, which has been ongoing since 1993, is a 123-acre site the city purchased from a steel company.

The city has sunk $103 million in public parking garages, park improvements, bridge renovation, infrastructure and remediation. The funds came from the budget of the Urban Redevelopment Authority of Pittsburgh, the state, parking garage revenue, the water and sewer department, tax-increment financing and Housing and Urban Development grants.

The private sector in Pittsburgh responded by investing $220 million on a mix of projects that include housing, office and retail developments.

Chattanooga, which wrapped up its redevelopment last year with Hargreaves, used a city bond issue in its mix of funding that's being paid through a hike in the local hotel/motel tax, says Ann Coulter, partner of Chattanooga-based Kennedy Coulter Rushing and Watson - one of the firms in Nashville's design team.

"It's a tax, but it's not on Chattanoogans," she says. The Chattanooga lodging industry saw such potential in the riverfront redevelopment they agreed to a nominal sales tax increase.

The upshot: Funding will likely be a public/private partnership, similar to many of Nashville's other redevelopment projects, says Gary Everton, partner in Everton Oglesby Architects, which is part of the design team.

As to how much will have to be shelled out on either end, Everton says it's just too early to generate a number.

The same goes for who will see the redevelopment through. "Leadership teams emerge as people get excited, as they realize there's a role they want to play or can play," Coulter says.

Other markets have controlled the redevelopment through government, nonprofit arms of the cities or mixes of both, McMillan said Aug. 24.

Chattanooga's RiverCity Co. is a private nonprofit that was formed to assist the city with riverfront redevelopment. In Fort Collins, Colo. a city-run redevelopment program was formed and approved by the city council. Saint John in New Brunswick formed a partnership funded by government, corporations and community organizations.

"Nashville will have a solution that works just for Nashville," Everton says.